1 files changed, 321 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
new file mode 100644
index 000000000..be8db402e
--- /dev/null
+++ b/arch/powerpc/kernel/paca.c
@@ -0,0 +1,321 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * c 2001 PPC 64 Team, IBM Corp
+ */
+
+#include <linux/smp.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+#include <linux/sched/task.h>
+#include <linux/numa.h>
+#include <linux/pgtable.h>
+
+#include <asm/lppaca.h>
+#include <asm/paca.h>
+#include <asm/sections.h>
+#include <asm/kexec.h>
+#include <asm/svm.h>
+#include <asm/ultravisor.h>
+
+#include "setup.h"
+
+#ifndef CONFIG_SMP
+#define boot_cpuid 0
+#endif
+
+static void *__init alloc_paca_data(unsigned long size, unsigned long align,
+				unsigned long limit, int cpu)
+{
+	void *ptr;
+	int nid;
+
+	/*
+	 * boot_cpuid paca is allocated very early before cpu_to_node is up.
+	 * Set bottom-up mode, because the boot CPU should be on node-0,
+	 * which will put its paca in the right place.
+	 */
+	if (cpu == boot_cpuid) {
+		nid = NUMA_NO_NODE;
+		memblock_set_bottom_up(true);
+	} else {
+		nid = early_cpu_to_node(cpu);
+	}
+
+	ptr = memblock_alloc_try_nid(size, align, MEMBLOCK_LOW_LIMIT,
+				     limit, nid);
+	if (!ptr)
+		panic("cannot allocate paca data");
+
+	if (cpu == boot_cpuid)
+		memblock_set_bottom_up(false);
+
+	return ptr;
+}
+
+#ifdef CONFIG_PPC_PSERIES
+
+#define LPPACA_SIZE 0x400
+
+static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit,
+					int cpu)
+{
+	size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
+	static unsigned long shared_lppaca_size;
+	static void *shared_lppaca;
+	void *ptr;
+
+	if (!shared_lppaca) {
+		memblock_set_bottom_up(true);
+
+		/*
+		 * See Documentation/powerpc/ultravisor.rst for more details.
+		 *
+		 * UV/HV data sharing is in PAGE_SIZE granularity. In order to
+		 * minimize the number of pages shared, align the allocation to
+		 * PAGE_SIZE.
+		 */
+		shared_lppaca =
+			memblock_alloc_try_nid(shared_lppaca_total_size,
+					       PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
+					       limit, NUMA_NO_NODE);
+		if (!shared_lppaca)
+			panic("cannot allocate shared data");
+
+		memblock_set_bottom_up(false);
+		uv_share_page(PHYS_PFN(__pa(shared_lppaca)),
+			      shared_lppaca_total_size >> PAGE_SHIFT);
+	}
+
+	ptr = shared_lppaca + shared_lppaca_size;
+	shared_lppaca_size += size;
+
+	/*
+	 * This is very early in boot, so no harm done if the kernel crashes at
+	 * this point.
+	 */
+	BUG_ON(shared_lppaca_size > shared_lppaca_total_size);
+
+	return ptr;
+}
+
+/*
+ * See asm/lppaca.h for more detail.
+ *
+ * lppaca structures must must be 1kB in size, L1 cache line aligned,
+ * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
+ * these requirements.
+ */
+static inline void init_lppaca(struct lppaca *lppaca)
+{
+	BUILD_BUG_ON(sizeof(struct lppaca) != 640);
+
+	*lppaca = (struct lppaca) {
+		.desc = cpu_to_be32(0xd397d781),	/* "LpPa" */
+		.size = cpu_to_be16(LPPACA_SIZE),
+		.fpregs_in_use = 1,
+		.slb_count = cpu_to_be16(64),
+		.vmxregs_in_use = 0,
+		.page_ins = 0, };
+};
+
+static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
+{
+	struct lppaca *lp;
+
+	BUILD_BUG_ON(sizeof(struct lppaca) > LPPACA_SIZE);
+
+	if (early_cpu_has_feature(CPU_FTR_HVMODE))
+		return NULL;
+
+	if (is_secure_guest())
+		lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu);
+	else
+		lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
+
+	init_lppaca(lp);
+
+	return lp;
+}
+#endif /* CONFIG_PPC_PSERIES */
+
+#ifdef CONFIG_PPC_64S_HASH_MMU
+/*
+ * 3 persistent SLBs are allocated here.  The buffer will be zero
+ * initially, hence will all be invaild until we actually write them.
+ *
+ * If you make the number of persistent SLB entries dynamic, please also
+ * update PR KVM to flush and restore them accordingly.
+ */
+static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit)
+{
+	struct slb_shadow *s;
+
+	if (cpu != boot_cpuid) {
+		/*
+		 * Boot CPU comes here before early_radix_enabled
+		 * is parsed (e.g., for disable_radix). So allocate
+		 * always and this will be fixed up in free_unused_pacas.
+		 */
+		if (early_radix_enabled())
+			return NULL;
+	}
+
+	s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu);
+
+	s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
+	s->buffer_length = cpu_to_be32(sizeof(*s));
+
+	return s;
+}
+#endif /* CONFIG_PPC_64S_HASH_MMU */
+
+/* The Paca is an array with one entry per processor.  Each contains an
+ * lppaca, which contains the information shared between the
+ * hypervisor and Linux.
+ * On systems with hardware multi-threading, there are two threads
+ * per processor.  The Paca array must contain an entry for each thread.
+ * The VPD Areas will give a max logical processors = 2 * max physical
+ * processors.  The processor VPD array needs one entry per physical
+ * processor (not thread).
+ */
+struct paca_struct **paca_ptrs __read_mostly;
+EXPORT_SYMBOL(paca_ptrs);
+
+void __init initialise_paca(struct paca_struct *new_paca, int cpu)
+{
+#ifdef CONFIG_PPC_PSERIES
+	new_paca->lppaca_ptr = NULL;
+#endif
+#ifdef CONFIG_PPC_BOOK3E_64
+	new_paca->kernel_pgd = swapper_pg_dir;
+#endif
+	new_paca->lock_token = 0x8000;
+	new_paca->paca_index = cpu;
+	new_paca->kernel_toc = kernel_toc_addr();
+	new_paca->kernelbase = (unsigned long) _stext;
+	/* Only set MSR:IR/DR when MMU is initialized */
+	new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR);
+	new_paca->hw_cpu_id = 0xffff;
+	new_paca->kexec_state = KEXEC_STATE_NONE;
+	new_paca->__current = &init_task;
+	new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	new_paca->slb_shadow_ptr = NULL;
+#endif
+
+#ifdef CONFIG_PPC_BOOK3E_64
+	/* For now -- if we have threads this will be adjusted later */
+	new_paca->tcd_ptr = &new_paca->tcd;
+#endif
+}
+
+/* Put the paca pointer into r13 and SPRG_PACA */
+void setup_paca(struct paca_struct *new_paca)
+{
+	/* Setup r13 */
+	local_paca = new_paca;
+
+#ifdef CONFIG_PPC_BOOK3E_64
+	/* On Book3E, initialize the TLB miss exception frames */
+	mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
+#else
+	/*
+	 * In HV mode, we setup both HPACA and PACA to avoid problems
+	 * if we do a GET_PACA() before the feature fixups have been
+	 * applied.
+	 *
+	 * Normally you should test against CPU_FTR_HVMODE, but CPU features
+	 * are not yet set up when we first reach here.
+	 */
+	if (mfmsr() & MSR_HV)
+		mtspr(SPRN_SPRG_HPACA, local_paca);
+#endif
+	mtspr(SPRN_SPRG_PACA, local_paca);
+
+}
+
+static int __initdata paca_nr_cpu_ids;
+static int __initdata paca_ptrs_size;
+static int __initdata paca_struct_size;
+
+void __init allocate_paca_ptrs(void)
+{
+	paca_nr_cpu_ids = nr_cpu_ids;
+
+	paca_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
+	paca_ptrs = memblock_alloc_raw(paca_ptrs_size, SMP_CACHE_BYTES);
+	if (!paca_ptrs)
+		panic("Failed to allocate %d bytes for paca pointers\n",
+		      paca_ptrs_size);
+
+	memset(paca_ptrs, 0x88, paca_ptrs_size);
+}
+
+void __init allocate_paca(int cpu)
+{
+	u64 limit;
+	struct paca_struct *paca;
+
+	BUG_ON(cpu >= paca_nr_cpu_ids);
+
+#ifdef CONFIG_PPC_BOOK3S_64
+	/*
+	 * We access pacas in real mode, and cannot take SLB faults
+	 * on them when in virtual mode, so allocate them accordingly.
+	 */
+	limit = min(ppc64_bolted_size(), ppc64_rma_size);
+#else
+	limit = ppc64_rma_size;
+#endif
+
+	paca = alloc_paca_data(sizeof(struct paca_struct), L1_CACHE_BYTES,
+				limit, cpu);
+	paca_ptrs[cpu] = paca;
+
+	initialise_paca(paca, cpu);
+#ifdef CONFIG_PPC_PSERIES
+	paca->lppaca_ptr = new_lppaca(cpu, limit);
+#endif
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	paca->slb_shadow_ptr = new_slb_shadow(cpu, limit);
+#endif
+	paca_struct_size += sizeof(struct paca_struct);
+}
+
+void __init free_unused_pacas(void)
+{
+	int new_ptrs_size;
+
+	new_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
+	if (new_ptrs_size < paca_ptrs_size)
+		memblock_phys_free(__pa(paca_ptrs) + new_ptrs_size,
+				   paca_ptrs_size - new_ptrs_size);
+
+	paca_nr_cpu_ids = nr_cpu_ids;
+	paca_ptrs_size = new_ptrs_size;
+
+#ifdef CONFIG_PPC_64S_HASH_MMU
+	if (early_radix_enabled()) {
+		/* Ugly fixup, see new_slb_shadow() */
+		memblock_phys_free(__pa(paca_ptrs[boot_cpuid]->slb_shadow_ptr),
+				   sizeof(struct slb_shadow));
+		paca_ptrs[boot_cpuid]->slb_shadow_ptr = NULL;
+	}
+#endif
+
+	printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
+			paca_ptrs_size + paca_struct_size, nr_cpu_ids);
+}
+
+#ifdef CONFIG_PPC_64S_HASH_MMU
+void copy_mm_to_paca(struct mm_struct *mm)
+{
+	mm_context_t *context = &mm->context;
+
+	VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
+	memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
+	       LOW_SLICE_ARRAY_SZ);
+	memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
+	       TASK_SLICE_ARRAY_SZ(context));
+}
+#endif /* CONFIG_PPC_64S_HASH_MMU */